The G5RV is up

G5RVF4The antenna situation has improved. There is progress on the hex beam, but in the meantime I’ve put up a G5RV. It is almost exactly the size of the largest run possible on my property. I had some difficulty getting enough angle on the trees to shoot the line and I am frankly surprised it all worked. The line is tied down to the tree trunk on one end, and the other loops over a tree, then through a metal loop screwed into the property wall, and that end suspends a brick, which maintains tension on the line but has enough give to allow tree motion. The center twin lead is centered over my house and I was not able to get the two arms of the antenna high enough to allow the feed line to hang down straight; this is not ideal as it will change the plane of radiation since the feed line is active in this design. I was also concerned about the feed line coming down too close to the metal roof, so I have arranged another support for the feed line, which pulls it close to horizontal. It also keeps it away from the high power security lights that rim the roof and which put out some RF.

I swept the antenna with an MFJ analyzer in the shack and the SWR is less than 3:1 on 80, 40, 20, 17 and 10m. I have had some good runs on 10, 17, and 20 meters, and a few contacts on 40m. Even on bands where it it not resonant, I’ve had reasonable success using a tuner; being able to run 100W gives me some margin for inefficiency. I worked one EU station after another one afternoon on 30m, and finally had a contact with Alain, 5R8AL, also in Madagascar on 12m. The additional power has allowed me to run a frequency on voice.  I’ve now set up the TS450 for digital communications and have had a few PSK31 contacts as well. I’ve getting some RF back, which is affecting the external USB sound card, so a near term project will be fixing station grounding.

wood mill workers milling the tree into a postAs for the hex beam, I finally have all materials. I visited a local lumber yard and had a 4m x 15cm x 15cm post milled. It arrived at my house on a cart and is now sitting across two chairs on my porch. I’ve given the post a coat of wood treatment (permethrin + cobalt salts) and will paint it for more protection. Meanwhile, an almost 2m deep hole has been dug in the backyard, and I’ve purchased about 200 kg of cement, which with some aggregate will become the base for the wooden support beam.

The plan is to get the base in place and set up a shelf using angle iron to support the G450 rotor. Further up the post, I will install a universal thrust bearing to handle the lateral load. A 10m spiderbeam telescoping mast will support the hex beam, and will itself be guyed at two levels. Finishing this project will await some good weather and enough time to see it through.

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